1. Field of the Invention
This invention relates to storage area networking using the Fibre Channel protocol. More particularly, it relates to storage area networks connected to blade-type file servers.
2. Description of the Related Art
The scaling of dynamic Fibre Channel fabrics is a challenging problem. When switches are added to or removed from a fabric they tend to precipitate high volumes of control traffic, causing the CPUs of the constituent switches to get overloaded, and often result in production data disruption due to fabric re-configurations. Fabrics also tend to become unstable while handling large volumes of fabric events. These issues are further exacerbated by the growing trend to blade servers. The host processor blades in the blade servers are intended to be hot-pluggable. Further, any Fibre Channel switch located on a blade would also be intended to be hot-pluggable. This makes fabrics even more dynamic and places increasingly higher scalability requirements on Fibre Channel fabrics. The hot-plug capabilities of these, possibly large, numbers of host and switch blades increases the probability of “event storms,” resulting in loading or disrupting the enterprise fabrics they are connected to. These problems may ultimately result in loss of service (e.g., host bus adapter logins may timeout) under heavy load conditions in the fabric. It would be desirable to be able to use host blades and switch blades in blade servers without having the problems discussed above.